SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef3b8130094d567805d7d7dee744ba686789d56b5ca899ee7c5f117c6e553cd9' 
  AND token = 'q7jfnL5oHmi0RLD7amAKmzFz8ugnqwwJONV9LqaCFKc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}