SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d5870b4f5f9dd8cbe012802716aac0a9c4e385b077f92db21789933b6b3e705' 
  AND token = 'JzmG4qN/oFL4MN4psOv8G3hhSb3iXrrS/oVIdPTGIxk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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