SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e796dae560562d87859be20e8c23f32b012afa110a73ade15163d7b9a978d552' 
  AND token = 'o9zvPoKtl7OJ+BKEONKz1C/NG4CM6SZcxh9ltyQJu+Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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