SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7be36d17a40588cdff5d94e6233d292c66cc74b2284d5e55e670e43a8a274823' 
  AND token = 'wJEFbdQ8yk4BWQgZegn+L25PE9Vld2cbee7r8jkNAnE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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