SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60424fc48a286f2113a729761ebe4ad229348e358fa79db6d6a83dfef5717ee5' 
  AND token = 'GCMwgcidubrjWfV2Nve+5hxJ0/TguKoTdmEeCzm5g7k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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