SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '86aadc03d0225b31c8371f33d58af76585f4f4022db836cb2a9d09e91b8dac1b' 
  AND token = 'DZT4Wy8WA1XmGXzU9gIt2xfEMzjNuzDemYWRFHjzWKQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}