SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '17b2f3d4b4f03ac895e9213c23c2f2c87a16d2e34526316c5a97f0f7da930ed1' 
  AND token = 'R+YXqWZG/tKbRfJRYi+qjuWo9h2DrGCEQnUWu5Zv1Ik=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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