SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b0c41385a2141030299c6152c78967fbc8c935bbcb4b6952f9b00f1aae274684' 
  AND token = 'eiLxK57cYOAl8/1X4xQJxGRhF0TdxqXZtDDLW86EJ2Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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