SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2660cecb51a067115203c67f48c21d9f139c9717cc83eb62077f8ce57990174c' 
  AND token = 'q2gVulPFrzNsUO5tF5plShrNilT4/bwYYQ9Kw1N6MkU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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