SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b706bc768540ef54d6d3fd0e6ce648b4907714a68d37a12c3f54c6a9c6a063a3' 
  AND token = 'vJ/gPrrr3CHRCLtJ5jmciBIo3TrcnAJrPW09qKQwzqQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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