SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60c4ca606e043ecc0efa7432e63be76321514cca215f44dbe3ed8567118e07b7' 
  AND token = 'RNhgpDq/6Th6XiY7oHD193rYgECVurZF5sBwwr+udDk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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