SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c3d409bcaca0a91891ff6ca68a1126034203a9d05f96ba91d41d44e4df97033' 
  AND token = 'JJiW3YRvmynnLN4wiDTNhN8COSPO6rxX2UjOwyhEB6s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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