SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '583a874b7b48c05bf616228ea028cc3d0dd070aab9c199f66b061eafb35fd10a' 
  AND token = 'sm/aOJzuxyeByWW853ijflfgDJMGgO+Aw4Ev2Y2yoek=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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