SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd4bc48abc899e3fdc9e8a81ef6124ec2bd4fd57d090a6e73f53037d625d5dcc' 
  AND token = '8yhY0t+GqXzJyDvj0UpBDakJK/lNKpu1CSBN/YS3ej4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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