SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7831fd65c27fcb836ffb3733d62dbcf05920989c4903d89020b08521428d1ecb' 
  AND token = 'p3VIpfpcN70zyx4rKSE8qycOJQZIo6AX+1sWcAnj6rA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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