SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '443eba81ed4d1f319f749b032b4c5a131f878f8cf87f57e2c34287c1009d9374' 
  AND token = 'eDXeVVJAcrToGHqWq5t70YmvDQ8a8cLcugakKuvrsxk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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