SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd0954cdba2d18be38e118f8959e1462c37c2cf2c3c098b452f8f148f30d094bf' 
  AND token = '46WmyHZLw5dh0XBcoyLs4unMC6nPMI+gg0mdQjhLWb8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}