SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59e359e1d1049b244b2660bbd151bd422bc7bb77378f66c95ecd03d54f18ef52' 
  AND token = 'hR47okpUFtatDfxl+dQi6SPi3yz/dqJj361qfzToOtM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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