SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '118e49ec9f333402b226dd6d72e42b48a8c48974e64030176b1ec11448387270' 
  AND token = 'rkTLkD/WIg6nypgHR9Hc3di9hJMwqEG+mhsR5pjOIBQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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