SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce5f3c75a2d448fb604d62d74e4040c0627b4f8fd824b26201959b08b835f89f' 
  AND token = 'Ul3DVV/z7/meqhwJMAglibIMYOF1vsNYH4WsJooK5n8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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