SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fea3f0bfab96b618ed8624716894ca7e063e62993a402bb176f2521084438911' 
  AND token = 'WpL0rhjIyotAa/Bh9/u52kMcNuWKMCK6QVBdEHTIoKo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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