SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b1f0f26655d17a17d0179b1a00f4652f9416ea5ddbc34b7719f0227a46c62083' 
  AND token = 'BGz1GR65GtoUPqgDA8XXqODs3va1lvdxY12Hjtw81EE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

JSON explain

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