SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '1be87991930b0a05488646ad59238e100d4b363ceee1abb2940713f97dac55c4' 
  AND token = 'aZGiHolOd5lGgvf6GhCNYNOWqTbq1e35juq5K1tPFFg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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