SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0087c2d53aae4f04142422d27e2ecfaf0e40d65e0fbc8e042dfbadd6190f4e31' 
  AND token = 'dokkXdSQQvhvxuzw1IPRb79sRBR6eDcy5LgEJFGa1NM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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