SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '890e91bbdbc06ebccd8cc1a3856b01c8eee608f552e1a5b22265e36b6429df48' 
  AND token = 'X8xtMq1/XqJ2kKepdisT/c7b2Or0revTkymDKR1EVus=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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