SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f8a9b32a461ff72136b86021cb52e2d396b2be33431d1f1f29bbee6d5fe246b3' 
  AND token = 'hnh8ntzz/w+aOxqguiOFb3ogDxfZGxLv9BPrA7MbRk0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}