SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '101b14aff6745d6a874e85142e6b3f628fd459c9d7c76aa4eeff372a94defc58' 
  AND token = 'e4V+Qd69MLRUc+g/+RwBCNEjQhxarLvpbtgleutQ3h0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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