SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '431622d8a2f11eb9d3ccb5cd78f9d9f06c235ddcadb6f1a06c38cd555f699592' 
  AND token = 'vI+8n3LWHQdwVJqweV+qqMfQjl44tXzcTRPRGJJcXLI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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