SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ba9a361b8e86e279f802d0f2f5653cadb3b2245c4e3eb7c89e6655f6144cb53' 
  AND token = 'OAYXrU072fe6UZ0FwqHIJ/wl6+qAH+nTWPx+4dBHXgY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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