SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '66edc6dd1d4864e4179cc7d40dbdf99ee26e65661543a48ef8b59a896c13013e' 
  AND token = 'fbGX28Wdo3cKyDe4LeOz1wDw8EjPQp+BGvYzFTkglWc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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