SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8494316b023442da4b2974de18314f082f80ebf27147f1a081a612b054cf1222' 
  AND token = 'YB4SfaPBBfaIKDFJ4dtS7kPHjkS/HBcSAaqYQYI2lnw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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