SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce753fa1ca9d72978fe3ad1b12c4c832e0cad2bd7b39fe73191df7fbad065ed0' 
  AND token = 'NkGsc68JBYDjmtELwlQICn/z2ADTzY7qZ8DwpweoQKY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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