SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f4c6164abcd4ead99f907b35b82c5f7990181643b6f3cce59a1dceb41dc2d6a2' 
  AND token = 'Kl+QhS5CirwVcijYoILBhp2v/qoXG2mU3VxSiHdhXFU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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