SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a1cf6df72f0584def25af5f66cdcd92cfbe5afd504ee7066bee89cb06798505' 
  AND token = 'I5vRoBKhwXZYkoCiMy4WIDhbKjVj1wNm7K+gEt9FSRo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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