SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06a901170748d8e1e8aa700b34bd4f85585c01adaf057fa4f465bc3b0612f7ea' 
  AND token = '5xDDtxIbM60TB+Wn8DPcMIifvQJUgZ7pPBTkQtWjD6Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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