SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4409e4d42932d1d7dca35a91a1d11a06655976954ec10101e3a2c269991d83c7' 
  AND token = '1kJ9aJGdrPreveSE1V8YTZG7v5Nn6a5OB0TNV/rhQT8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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