SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92efce5642846de92e65c0aafc2ee73895621981bb5c514363b72a19fc642798' 
  AND token = 'bpzJ8r9+VY3YJTJB5GRIUqmJ5frECzK0La/kcLT66wY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00066

JSON explain

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