SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58b0cd48ee6ffb7445f377a4ebde854f3850eccaf978f2c487fa96c316b57a3e' 
  AND token = 'jvypJmWNXlFgf/w0wxLvpbBJPOta8umupjkLNd6OuKg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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