SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca01128708fd27398ce9a2771e99a11bdfb623ea4fd456268e8d0030140fa331' 
  AND token = 'PFptXrt6h029qi3zFBD7qDS8Y1ifXm+2ylXg5vmXwB8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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