SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '641c09c87095abf0e4e01c6e483892abfc5f8eac35414f769fabbbbb2c9a2f3f' 
  AND token = 'ZSlA+YjK7Yf+F2zl2rq10uJFG0uSgvLw+cO2mvBcPNY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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