SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64291cd3b0a78ca091e247ff710a4b24f29f431eb59e0a1d1821e4bb62aa7a8f' 
  AND token = 'mNwSxB+QwYo4OkIt7vyjHbGKLJ6FPFheCWc8z/qwN4g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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