SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '507e3272557afc15d99cffe7dda58622ee4bf086bfb8581d51029b1057a5541e' 
  AND token = 'TuWELjXcJYU9iPvuh9DO78zNmte8M+KSl+gNYX1mwpo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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