SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '22f23dcabbc33f743a3c77300357153932e9cb94f73c38102c320dd21af79129' 
  AND token = 'DjHSL7Pn310LDj+7t5VM5sLBUEG4L+u3VlUeJ7MGubQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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