SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab5ab6dc452c1c36f8b779356d09c1446af34fcf0b4a901c04b35f2532314fde' 
  AND token = '32hMmxyeR5qbvyyTsWNLGNFWK3qbNPjJVQrcqoerhpk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00054

JSON explain

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