SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a69f214b634b2f043b2594e17a329aa718be88f07a77ed2d8502fbc2371396ec' 
  AND token = 'WtKTvgghq3YC/CzRfkVZ+Oy++CYM7FYjAfmH+G7TMak=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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