SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7826daf4953ba1bfbef039bc7aef1a92deaeecb445d78267ef31d9d7a5dd8b10' 
  AND token = 'IxEGPPg7XXAsVJDrkyOigR6Tzd1QFYjq+CvbbCxhG8o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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