SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5926ea2e1e74fc17a20f55be12120ccb1ab8089926eb84a37d3230155365d15b' 
  AND token = 'RnuXN+zuH9n2PGQbSpYKhX7S6KUw+JkCIz2BCPs+3zM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00069

JSON explain

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