SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0db6de25950558af44c429d5d836816e2e655e7dcce2c6d68b02cd97c10d1a03' 
  AND token = 'hV4gMBBgBRF/PJj3OeSKC+gXKuxLFQVVgPgI88tvxVM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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