SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '66313c2ab3d9a90ef07625d74a91fe4b048518595b380177d3ea1beb86aeaae8' 
  AND token = 'mPSydejzh7Hfo5dZ2BQOWPM1bY21bs2JNXOisKYOkhA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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