SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8432b0986e4f5aa173dcd91289f27d45d0134bfe0ab7a03b9da9b9d7358877a6' 
  AND token = '01FL7ftrfdJXUoQHAFIWfCoXD5aGEaww0AfQHxALoao=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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