SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c153dbd27475fa3859c888346c676a9f185773fd2f8b438d7a657b5f210d01a8' 
  AND token = 'ZINEXJhHtHS4oak+J1J1xBAEih4HwXEQl2BDBKazWVI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}