SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '901fd3e96350c35cbd140560aa6f6d18914209ac68df4cfa45105b9e99679229' 
  AND token = 'EH2kWuaFU4XvBfLDs1GEGRkqBKl54985yWYJjzDf9Po=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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