SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46b6d9a86ac4e16717d34b60a4d1386c59ac39a8e9529c8e6a91163f094e2165' 
  AND token = 'vZjZTs5LDWgzbqWSTwsqqGuaZ9fhOFmZfQVb/hgFQo0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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