SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e85921e6db5f59a8c2e64c7f6bdd0db1d6860b68468cdbfa73fbab82a660cad4' 
  AND token = 'FU1lXti3EeP7ldr1iQcuk7KRqQCBMS5rL8cC/5i0UJc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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