SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '55d76a5e91218e372b36731680cc2b4fb6d3a0c0af584588fb81cf55a6c91424' 
  AND token = 'c127CH6WDtgWwWQ9xuhVeNijRGFBRKIm4fJLBTLARo4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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