SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f464c154ccc716e9183c56a1957484c65f363421265fbeb08782a0f715f4d2e' 
  AND token = 'ufNNvDmFmZuK1hwDh5AcX52+EXA5aLBTlUobO8PH4dY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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