SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '62a201d611955ea6bfb6bb815a327328c45973e120c688302c9d4b4734ae4a6a' 
  AND token = 'jqg9b3eyyK4dEBjh/RAC2dSqrgMXxvxxWP2sG2b9tFI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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