SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '927c0a75b43d55783ff3c78dc88eee59196acac9a20376641ccdf3f3756bce6d' 
  AND token = 'vF0AKfZQAwmY3fJxmg15FLJvibKw1qghmtulVLRcPpg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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