SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9bbff6f12eeda0ce68e38e6bfea6c423b989270987d1f08264b824eb8ce9326' 
  AND token = 'zEtS0H9x4dFdbCmc69HLVEi9LfXUC+Ex71Pr3C+rYu0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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