SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e261a34fc5c5f24b84db0d141579398d954e99962a850723ebc47d300caf8f2' 
  AND token = 'vWYjidSt+CwBGImg8xaUEHRCmm14njR4jIolVL6QAh4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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