SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25265ef4513d13a7845b6ef67c816a3222ce9d6a8aaff54136d3c9d5b64fff5f' 
  AND token = 'MbU3/VQKhABUhwg6t0Vhfm6IBhnhPrfk/YAvjuVGBXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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