SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74cf676b4986525784f9ed2f6a9c6621b6e9b38b1f66444dc8ffc55bdd3c0874' 
  AND token = 'yRgG0W/ipDyOBH7LnNnj5YfKoVHEJ2qVRHgXA9SbGOY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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