SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f80b8f630b3fa97b17f45c04ec32514fb713aa552d132f5ac80857c6912c3dc9' 
  AND token = 'hCjlrd+y9wCKXZGiTkVcANqmT0yGvc3iDtuC4E0/nYY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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