SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4ef04dea2047b87797e9b72b010f20a2b3cc4f21abb9203e0dd2f827155fd84c' 
  AND token = 'aYVQRscsMW5UK/LEzAXQRj8DGZ6vY6/O4B5V0te5P7s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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