SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '989b373cbe071cbd4ed54c55ed9bf6e91bc2f44ff816ca0c7a257aba38b80023' 
  AND token = '+ZIzCohJfVq1OR51irlhgbIhjd4DL+IyEj9o6psRwcQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}