SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f0719b37ba53823855b0ff93496482105f0bc4610ad2f11945d4974c6e465d5b' 
  AND token = 'N0myXBcRYi0MrjkyxgrI4uMfZwmxKzMmt9WyXea9U3g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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