SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6c61a4d095e157a549974f318dae0330276c0fbd37f24bc2e9786ad6076518b6' 
  AND token = 'p3CBV+lY6PNsfzDSRhZeCa5IZtl/b4yRqFbFG889Anw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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