SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4448d3835ac6300de15f3e97e51e6f99f65b90267449559b422f565553f08d19' 
  AND token = 'GOMfJDM8Aq0MkLJjz1T+3V2hPprygGwv9yO+3+iusAE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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