SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '112abf0d1c29f6b82372984de935b5f1f3eca71e25dca83a85d538bedcb14cad' 
  AND token = 'zJ+uVoiLRqEntzo7JzymtP5M7Kg1bTBnJXpqmt3C3dw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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