SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '165ec3002a0f980a2111ad57bf8ab51db485905d08e2cad881e815bdf3174faf' 
  AND token = 'PQvdtnZNoe4odqIaJN0moEkoFQxk8h6F3WaUPumaniM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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