SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f7178a6619d4789e640fbbe74be0e0cc7033a35250f4aae29647627c3cdcc95' 
  AND token = 'xtQlVTc85kgM2wWYPz1LnM4sBEQgVH42tF67icmXcJs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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