SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b077b49ed9e7922de4d7add4f2ed606062a799586d762b146bfe62b60a10ec2e' 
  AND token = 'MMfmBZVCwbpK5fVhC+5k5G3i2d/5EJqy0MCXvcDLKic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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