SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '926777caa5a7b7a85bf44f9da7a83d159e6682977de36f7f52d3dc14cb280fdc' 
  AND token = 'zrbq/+hr2kJtV/J2Uzb3hmgyf2lBAPbj17UuHF7UJj8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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