SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b95f85c00342c334679e1ea49ebe6b35ad0533fa962b1f33a11e9e489fd38ee6' 
  AND token = 'edfmKZnkHAybpzWCC4xoC+Y3zpSWUoan0tuVi9Dhfac=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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