SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8a6e1af36279fa3ea616b212ef23cc47b7b3ebd2b40b4e4bfcc0972f58d17105' 
  AND token = 'fkhGzYwig75aL+cgBf9O5XxNGD7Ddzz6KoY0rSJpAlc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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