SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '37ba1881b436b8b815f45db605c5e31ed72734209b573337a333b5fe0f6baba6' 
  AND token = 'Qwa/j9Y7YXIVoB7EtBvgzMxK7JxCNn1X3hJcwbR2PV0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}