SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '979ce396162995a025f271319056ff59eec5ee898b010db0c51e1ec2dc5255a7' 
  AND token = 'wLuXkCfKUvoAjYjMDOWU1btnBJ/cFvt7ZzeqJF0nK4M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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