SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1b62a30cc916976ba73801bd862d0afd4775cc6f3c6ce04918b79cb0c537995c' 
  AND token = 'dLH63dRYj6kXwToZiq5Bdz/XwqsUpTdJRbVDRwL2TFk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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