SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '08073068882bd901b5c208b46c628706b4417e0c5859e10f9414dc2e9c9e48e9' 
  AND token = 'otlnSn5DSZce3F1qkF2CevKIgzoKGCzUs7JNJ12rjNc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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