Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '375efc0186a65fc2907951e8273de89f0750143a4ef00c1ebb2fdc51cffd4e76' 
  AND token = '0tdlNe81o8S+Hq5cXJgHvd1WHegHO4rR/cQQVCwwPgQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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