SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9df24363f254fd07995e8ac0e468f9bea10ba7d6f59d2645965b271b94e602a9' 
  AND token = 'x4MMdXtH/aMODcLBc/LiMFuLzqxygfTCiexxPCO/X9I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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