SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '668b06447b54f08c88931192c2ba290741b9c9ff7d49edcbaa6558c6cf56f6e7' 
  AND token = '7Ofs/5kQd9nZwYc1tD++CjL0Zf2YjVAbn5ZGFdrntUk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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