SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7dc9fc65dbf1cf99473d1932511874597ffcb93b45a945a796c1f6e43cfc5157' 
  AND token = 'qoS4mgEmja8WROXIIoVN4JuXCeJmfcUQ8pkX6op6L8Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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