SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc4d8b8302ced23a1bede3caf5c26f0399aa83ad666259c677d44a64fccda91f' 
  AND token = '6FQZLVh6uLwGfFiLFzUotA+zX9iFHz0Sxt8wasBJGxY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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