SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07c7e683bed30dccac9d8288c1975d730d377bc660914e3f72caf42b61a27642' 
  AND token = 'Krwmj3byghD5BWFNpmZ0aYB0t7wY8OJiGEV9mcgpV/E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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