SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ae0f88334322f8d37fbc9506c75a0f6b6c3668b915a402be92cdfc3829ac5d1' 
  AND token = 'X2lvbELxgwHIitM9JBNdvGVosQUVkQuRD1WfFfh/oFE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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