SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc6641e95331ffb4e0b2ed769545a712edaeda137cabd6f6710fd6cfa91cd94f' 
  AND token = 'TkRr8dblIJGaV48aQIJu+8JCXaCNizDV6RuT1YPEun8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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