SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ecb7994fbd8aeb528116ef0958903a60c0879024af39f96376b4ab12db8c625e' 
  AND token = 'ItRulhP1TB9waztESvDlSsaoY4tPJZFz5HH0pFrqhdI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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