SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f7b53c7fd857001c3340df17060f4f6408134efbaec54852dd9c3802ddea99e1' 
  AND token = 'tmhmsgtnUORRhNdP0ZSX36SqecqlIWURBzs4AoTQzxI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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