SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1c27ded5a455828d5e4c33287bc6010e515e06b713e2c2fc0709dbc0aeadab7' 
  AND token = 'Gciuetb624LBV0LnSS5h4XuPlfCzHhKJI1K+pPvYVhE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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