SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '024fb021f521fe300d39323eae92804b2b645ed99849d8c85c72c3dd7f056a5a' 
  AND token = 'L21zc6FjpOb9dgvWZNKL5B/6U+t0TZUFP6DTYgrDamw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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