SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ffbd8e0342040acc64503f14cf4889ad2d9e92a7f5b65699b7277c466abcaba8' 
  AND token = 'o1wgTHyxNQCE4OVg04jdSyc7hSPCMJXFTkvvM2gj6CY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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