SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '894f4f1635a505f3f9efb1c628e694031c6602218c3744d4d1dd11bdd5956b07' 
  AND token = 'k0im0OD1pLd0syLPJUVivPiKBlhUDLqlKGffpQDGn/Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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