SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92242220ef1c8775aea506c2f28a4dd9cac776867d081f75bbe688cac6e311c1' 
  AND token = 'fBJrIbOBAibbyNH4UsI+3xCq94dyZBwPG6XPVyyJVY4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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