Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '71b7bab6edb6b9aca2f88f87d8c4131c979556afa24a88a6c3fcf678d48b174c' 
  AND token = 'mVR8TWBcAiz8xneTYRaNr3/VID+d7+WAY4zQoD+Aedg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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