SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '012e8b56bc2b5be4a5f2162760fe1972d0aaed527f05792f75e23b53c05eeb11' 
  AND token = 'wrbbzPhnxrnh5pDRzbzD+bXJts8Pvrne8mgHU4WZs9w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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