SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c22cecfb49b3aa6a4192f1bb7a1cc5d0b4b738054cf24eeec3df2faeed9a5a6d' 
  AND token = 'OzU72vAu4zIgQYzvylV/BOVh1idULUAtKKcy3SHbekQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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