SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59b60f6d86b9636ab67a24907b7facbb3a00207c3c776551b758a4472d11d17c' 
  AND token = 'AKfPCcsLzSWbjQjQfN3d49+r/sYPXDU1CIsxBGRBUsg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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